Wildlife photographer Paul Nicklen was on assignment in Antarctica when he came across the area's most deadly predator - the aggressive leopard seal. While leopard seals generally reserve their bloodlust for their favorite food - penguins - they have been known to kill humans. Nicklen was well aware of this aggressive streak, and feared for his life. But what happened next was both shocking and absolutely heartwarming.

You're not going to find any cute animal photos on the Nature is Metal Instagram or subreddit. Instead, the sites focus on the gruesome side of the natural world, opting to feature the often bloody and sad reality of the food chain. Though much of the content is not for the faint of heart, there are a couple non-disturbing gems: a hilariously awkward giraffe showdown, and an alligator's failed attempt at having elephant for dinner.